diff -r 1756beed417c Lib/test/test_readline.py
--- a/Lib/test/test_readline.py	Sat Dec 17 09:19:11 2016 +0100
+++ b/Lib/test/test_readline.py	Sun Dec 18 16:07:46 2016 +0100
@@ -171,16 +171,21 @@
 if set_pre_input_hook:
     set_pre_input_hook(pre_input_hook)
 
+x = []
 def completer(text, state):
+    x.append('%s-%d' % (text, state))
     if text == "t\xEB":
         if state == 0:
             print("text", ascii(text))
             print("line", ascii(readline.get_line_buffer()))
             print("indexes", readline.get_begidx(), readline.get_endidx())
+            x.append('GOT 1')
             return "t\xEBnt"
         if state == 1:
+            x.append('GOT 2')
             return "t\xEBxt"
     if text == "t\xEBx" and state == 0:
+        x.append('GOT 3')
         return "t\xEBxt"
     return None
 readline.set_completer(completer)
@@ -192,6 +197,7 @@
 
 print("result", ascii(input()))
 print("history", ascii(readline.get_history_item(1)))
+print('completer', x)
 """
 
         input = b"\x01"  # Ctrl-A, expands to "|t\xEB[after]"
@@ -200,6 +206,7 @@
         input += b"x\t"  # Complete "t\xEBx" -> "t\xEBxt"
         input += b"\r"
         output = run_pty(script, input)
+        print(output)
         self.assertIn(b"text 't\\xeb'\r\n", output)
         self.assertIn(b"line '[\\xefnserted]|t\\xeb[after]'\r\n", output)
         self.assertIn(b"indexes 11 13\r\n", output)